Structured polydiorganosiloxane polyamide containing devices and methods

ABSTRACT

Devices including a polydiorganosiloxane polyamide containing material having a microstructured surface are disclosed herein. Such devices can optionally include a flex circuit attached to the microstructured surface and can be useful, for example, in fluid handling applications.

BACKGROUND

Fluid handling capabilities can be required in devices that can be usedin a wide variety of applications. For example, a device may requirefluid handling capabilities for collecting a fluid for subsequentanalysis, for transporting a fluid to storage, for liquid processing, orcombinations thereof. Depending on the specific application, there maybe a need for devices that can handle a wide range of fluids havingvarying properties. For example, a wide variety of devices having thecapability of collecting, handling, and/or transporting variousbiological fluids can be used, for example, in medical treatments anddiagnostic procedures.

To meet the need for devices with fluid handling capabilities, there isa need for new materials that can be incorporated into devices toinfluence the fluid handling capabilities of such devices. Further,there is a desire for new methods of making such fluid handling devicesthat can, for example, simplify the manufacturing of such devices.

SUMMARY

In one aspect, the present disclosure provides a device (e.g., a fluidhandling device) including a polydiorganosiloxane polyamide containingmaterial having a microstructured surface that can include, for example,one or more channels and/or wells. In some embodiments, the devicefurther includes a flex circuit attached to the microstructured surface.For embodiments in which the device is a fluid handling device, thedevice can be a capillary device. The microstructured surface can behydrophobic or hydrophilic, and is typically hydrophilic when used forhandling aqueous fluids.

In another aspect, the present disclosure provides a fluid handlingdevice that includes: a flex circuit; and a structured material (e.g., amicrostructured material) attached to the flex circuit, wherein thestructured material includes one or more polydiorganosiloxanepolyamides. In certain embodiments, the structured material is adhereddirectly to at least a portion of the flex circuit, sometimes withoutadditional adhesive. The flex circuit can include, for example, apolyester substrate such as a polyethylene terephthalate (PET)substrate. The fluid handling device can optionally include a source ofpotential.

In another aspect, the present disclosure provides a method of making afluid handling device. In one embodiment, the method includes: providinga structured material including one or more polydiorganosiloxanepolyamides; and attaching the structured material to a flex circuit,oftentimes a film-based flex circuit. The flex circuit can include, forexample, a polyester substrate such as a polyethylene terephthalatesubstrate. The structured material can be attached to the flex circuit,for example, by heating and/or applying pressure to the structuredmaterial. In certain embodiments, the structured material canadvantageously be attached to the flex circuit without the use of anadditional adhesive. In other certain embodiments, the device canadvantageously be prepared without the use of lithographic methods(e.g., photolithographic methods) and/or other wet chemical processes.

In still another aspect, the present disclosure provides a method ofmaking a fluid handling device. The method includes: forming amicrostructured surface on a surface of a polymeric material includingone or more polydiorganosiloxane polyamides; and attaching themicrostructured surface to a flex circuit.

As used herein, “a,” “an,” “the,” and “at least one” are usedinterchangeably and mean one or more than one.

As used herein, the term “comprising,” which is synonymous with“including” or “containing,” is inclusive, open-ended, and does notexclude additional unrecited elements or method steps.

The words “preferred” and “preferably” refer to embodiments of theinvention that may afford certain benefits, under certain circumstances.However, other embodiments may also be preferred, under the same orother circumstances. Furthermore, the recitation of one or morepreferred embodiments does not imply that other embodiments are notuseful, and is not intended to exclude other embodiments from the scopeof the invention.

As used herein, the term “or” is generally employed in its senseincluding “and/or” unless the content clearly dictates otherwise.

The term “and/or” means one or all of the listed elements or acombination of any two or more of the listed elements.

The term “alkenyl” refers to a monovalent group that is a radical of analkene, which is a hydrocarbon with at least one carbon-carbon doublebond. The alkenyl can be linear, branched, cyclic, or combinationsthereof and typically contains 2 to 20 carbon atoms. In someembodiments, the alkenyl contains 2 to 18, 2 to 12, 2 to 10, 4 to 10, 4to 8, 2 to 8, 2 to 6, or 2 to 4 carbon atoms. Exemplary alkenyl groupsinclude ethenyl, n-propenyl, and n-butenyl.

The term “alkyl” refers to a monovalent group that is a radical of analkane, which is a saturated hydrocarbon. The alkyl can be linear,branched, cyclic, or combinations thereof and typically has 1 to 20carbon atoms. In some embodiments, the alkyl group contains 1 to 18, 1to 12, 1 to 10, 1 to 8, 1 to 6, or 1 to 4 carbon atoms. Examples ofalkyl groups include, but are not limited to, methyl, ethyl, n-propyl,isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, cyclohexyl,n-heptyl, n-octyl, and ethylhexyl.

The term “alkylene” refers to a divalent group that is a radical of analkane. The alkylene can be straight-chained, branched, cyclic, orcombinations thereof. The alkylene often has 1 to 20 carbon atoms. Insome embodiments, the alkylene contains 1 to 18, 1 to 12, 1 to 10, 1 to8, 1 to 6, or 1 to 4 carbon atoms. The radical centers of the alkylenecan be on the same carbon atom (i.e., an alkylidene) or on differentcarbon atoms.

The term “alkoxy” refers to a monovalent group of formula —OR where R isan alkyl group.

The term “alkoxycarbonyl” refers to a monovalent group of formula—(CO)OR where R is an alkyl group and (CO) denotes a carbonyl group withthe carbon attached to the oxygen with a double bond.

The term “aralkyl” refers to a monovalent group of formula —R^(a)—Arwhere R^(a) is an alkylene and Ar is an aryl group. That is, the aralkylis an alkyl substituted with an aryl.

The term “aralkylene” refers to a divalent group of formula—R^(a)—Ar^(a)— where R^(a) is an alkylene and Ar^(a) is an arylene(i.e., an alkylene is bonded to an arylene).

The term “aryl” refers to a monovalent group that is aromatic andcarbocyclic. The aryl can have one to five rings that are connected toor fused to the aromatic ring. The other ring structures can bearomatic, non-aromatic, or combinations thereof. Examples of aryl groupsinclude, but are not limited to, phenyl, biphenyl, terphenyl, anthryl,naphthyl, acenaphthyl, anthraquinonyl, phenanthryl, anthracenyl,pyrenyl, perylenyl, and fluorenyl.

The term “arylene” refers to a divalent group that is carbocyclic andaromatic. The group has one to five rings that are connected, fused, orcombinations thereof. The other rings can be aromatic, non-aromatic, orcombinations thereof. In some embodiments, the arylene group has up to 5rings, up to 4 rings, up to 3 rings, up to 2 rings, or one aromaticring. For example, the arylene group can be phenylene.

The term “aryloxy” refers to a monovalent group of formula —OAr where Aris an aryl group.

The term “carbonyl” refers to a divalent group of formula —(CO)— wherethe carbon atom is attached to the oxygen atom with a double bond.

The term “halo” refers to fluoro, chloro, bromo, or iodo.

The term “haloalkyl” refers to an alkyl having at least one hydrogenatom replaced with a halo. Some haloalkyl groups are fluoroalkyl groups,chloroalkyl groups, or bromoalkyl groups.

The term “heteroalkylene” refers to a divalent group that includes atleast two alkylene groups connected by a thio, oxy, or —NR— where R isalkyl. The heteroalkylene can be linear, branched, cyclic, orcombinations thereof and can include up to 60 carbon atoms and up to 15heteroatoms. In some embodiments, the heteroalkylene includes up to 50carbon atoms, up to 40 carbon atoms, up to 30 carbon atoms, up to 20carbon atoms, or up to 10 carbon atoms. Some heteroalkylenes arepolyalkylene oxides where the heteroatom is oxygen.

The term “oxalyl” refers to a divalent group of formula —(CO)—(CO)—where each (CO) denotes a carbonyl group.

The terms “oxalylamino” and “aminoxalyl” are used interchangeably torefer to a divalent group of formula —(CO)—(CO)—NH— where each (CO)denotes a carbonyl.

The term “aminoxalylamino” refers to a divalent group of formula—NH—(CO)—(CO)—NRd- where each (CO) denotes a carbonyl group and Rd ishydrogen, alkyl, or part of a heterocyclic group along with the nitrogento which they are both attached. In most embodiments, Rd is hydrogen oralkyl. In many embodiments, Rd is hydrogen.

The term “polyvalent” refers to a group having a valence of greater than2.

The terms “polymer” and “polymeric material” refer to both materialsprepared from one monomer such as a homopolymer or to materials preparedfrom two or more monomers such as a copolymer, terpolymer, or the like.Likewise, the term “polymerize” refers to the process of making apolymeric material that can be a homopolymer, copolymer, terpolymer, orthe like. The terms “copolymer” and “copolymeric material” refer to apolymeric material prepared from at least two monomers.

The term “polydiorganosiloxane” refers to a divalent segment of formula

where each R¹ is independently an alkyl, haloalkyl, aralkyl, alkenyl,aryl, or aryl substituted with an alkyl, alkoxy, or halo; each Y isindependently an alkylene, aralkylene, or a combination thereof; andsubscript n is independently an integer of 0 to 1500.

The terms “room temperature” and “ambient temperature” are usedinterchangeably to mean temperatures in the range of 20° C. to 25° C.

The above summary of the present invention is not intended to describeeach disclosed embodiment or every implementation of the presentinvention. The description that follows more particularly exemplifiesillustrative embodiments. In several places throughout the application,guidance is provided through lists of examples, which can be used invarious combinations. In each instance, the recited list serves only asa representative group and should not be interpreted as an exclusivelist.

BRIEF DESCRIPTION OF THE DRAWING

FIGS. 1a and 1b are schematic diagrams used to illustrate interaction ofa liquid on a surface.

FIG. 2 is a cross-sectional cutaway view of an illustrative embodimentof a structured surface having channels within channels.

FIG. 3 is a schematic diagram of a device that includes apolydiorganosiloxane polyamide containing material.

FIG. 4 is a schematic diagram of a device that includes a layer of apolydiorganosiloxane polyamide containing material.

FIG. 5 is a schematic diagram of a fluid handling device that includes apolydiorganosiloxane polyamide containing material and a substrate.

FIG. 6 is a schematic diagram of a fluid handling device that includes apolydiorganosiloxane polyamide containing material and a flexiblecircuit.

FIG. 7 is a schematic diagram of a device that includes a structuredmaterial and a substrate.

The above brief description of drawings illustrating various embodimentsof the present invention is not intended to describe each embodiment orevery implementation of the present invention. Rather, a more completeunderstanding of the invention will become apparent and appreciated byreference to the following description and claims in view of theaccompanying drawings. Further, it is to be understood that otherembodiments may be utilized and structural changes may be made withoutdeparting from the scope of the present invention.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The present disclosure relates to devices that include apolydiorganosiloxane polyamide containing material. Such devices can beused in many applications. In some embodiments, a polydiorganosiloxanepolyamide containing material can be used in devices, e.g., devices thatcan control or transport fluids. In some embodiments, devices include apolydiorganosiloxane polyamide containing material having a structuredsurface that can control or transport fluids.

As used herein, a “structured material” refers to a material thatincludes at least one surface having features that may or may not bemicroscopic. As used herein, a “microstructured material” refers to amaterial that includes at least one surface having one or moremicroscopic features.

As used herein, a “microstructured” surface means that the surface has aconfiguration of features in which at least 2 dimensions of the featuresare microscopic. As used herein, the term “microscopic” refers tofeatures of small enough dimension so as to require an optic aid to thenaked eye when viewed from a plane of view to determine its shape. Onecriterion is found in Modern Optical Engineering by W. J. Smith,McGraw-Hill, 1966, pages 104-105 whereby visual acuity “is defined andmeasured in terms of the angular size of the smallest character that canbe recognized.” Normal visual acuity is considered to be when thesmallest recognizable letter subtends an angular height of 5 minutes ofarc on the retina. At a typical working distance of 250 mm (10 inches),this yields a lateral dimension of 0.36 mm (0.0145 inch) for thisobject.

A microstructured surface can include few or many microscopic features(e.g., tens, hundreds, thousands, or more). The microscopic features canall be the same, or one or more can be different. The microscopicfeatures can all have the same dimensions, or one or more can havedifferent dimensions. For example, a microstructured surface can includefeatures that are precisely replicated from a predetermined pattern andcan form, for example, a series of individual open capillary channelsthat extend along a major surface. These microreplicated channels formedin sheets, films, or tubes can be uniform and regular alongsubstantially each channel length and can be uniform from channel tochannel.

In some embodiments, the microstructured surface includes a regularlyrepeating pattern of microscopic features. In some embodiments, amicrostructured surface includes microscopic features that are notarranged in regularly repeating patterns.

As used herein, a polydiorganosiloxane polyamide containing material isa material that includes one or more polydiorganosiloxane polyamides.Thus, at least a portion of the material, and in certain embodiments allof the material, includes one or more polydiorganosiloxane polyamides.In some embodiments the polydiorganosiloxane polyamides can beelastomeric. In certain embodiments, polydiorganosiloxane polyamides canbe thermoplastic elastomers. For example, the polydiorganosiloxanepolyamides can be polydiorganosiloxane polyamide block copolymers.

Polydiorganosiloxane polyamide block copolymers can be linear orbranched. As used herein, the term “branched” is used to refer to apolymer chain having branch points that connect three or more chainsegments. Examples of branched polymers include long chains havingoccasional and usually short branches including the same repeat units asthe main chain (nominally termed a branched polymer). Branchedpolydiorganosiloxane polyamide block copolymers can optionally formcross-linked networks.

Polydiorganosiloxane polyamide block copolymers can have many of thedesirable features of polysiloxanes such as low glass transitiontemperatures, thermal and oxidative stability, resistance to ultravioletradiation, low surface energy and hydrophobicity, and high permeabilityto many gases. Additionally, the copolymers can have improved mechanicalstrength and elastomeric properties compared to polysiloxanes and linearpolydiorganosiloxane polyamide block copolymers. At least some of thecopolymers are optically clear, have a low refractive index, or both.

An exemplary polydiorganosiloxane polyamide block copolymer contains atleast one repeat unit of Formula I-a:

In this formula, each R¹ is independently an alkyl, haloalkyl, aralkyl,alkenyl, aryl, or aryl substituted with an alkyl, alkoxy, or halo. G isa residue unit equal to the formula G(NHR³)_(q) minus the q —NHR³groups, and q is an integer greater than or equal to 2. In certainembodiments q can, for example, be equal to 2, 3, or 4. Group R³ ishydrogen or alkyl (e.g., an alkyl having 1 to 10, 1 to 6, or 1 to 4carbon atoms) or R³ taken together with G and with the nitrogen to whichthey are both attached forms a heterocyclic group (e.g., R³HN-G-NHR³ ispiperazine or the like). Each Y is independently an alkylene,aralkylene, or a combination thereof. Subscript n is independently aninteger of 0 to 1500 and the subscript p is an integer of 1 to 10. EachB is independently a covalent bond, an alkylene of 4-20 carbons, anaralkylene, an arylene, or a combination thereof. When each group B is acovalent bond, the polydiorganosiloxane polyamide block copolymer havingrepeat units of Formulas I-a is referred to as a polydiorganosiloxanepolyoxamide block copolymer, and preferably has repeat unit of FormulasI-b as shown below. Each asterisk (*) indicates a site of attachment ofthe repeat unit to another group in the copolymer such as, for example,another repeat unit of Formula I (I-a or I-b).

A preferred polydiorganosiloxane polyoxamide block copolymer contains atleast one repeat unit of Formula I-b:

In this formula, each R¹ is independently an alkyl, haloalkyl, aralkyl,alkenyl, aryl, or aryl substituted with an alkyl, alkoxy, or halo. G isa residue unit equal to the formula G(NHR³)_(q) minus the q —NHR³groups, and q is an integer greater than or equal to 2. In certainembodiments q can, for example, be equal to 2, 3, or 4. Group R³ ishydrogen or alkyl (e.g., an alkyl having 1 to 10, 1 to 6, or 1 to 4carbon atoms) or R³ taken together with G and with the nitrogen to whichthey are both attached forms a heterocyclic group (e.g., R³HN-G-NHR³ ispiperazine or the like). Each Y is independently an alkylene,aralkylene, or a combination thereof. Subscript n is independently aninteger of 0 to 1500 and the subscript p is an integer of 1 to 10. Eachasterisk (*) indicates a site of attachment of the repeat unit toanother group in the copolymer such as, for example, another repeat unitof Formula I (I-a or I-b).

Suitable alkyl groups for R¹ in Formula I (I-a or I-b) typically have 1to 10, 1 to 6, or 1 to 4 carbon atoms. Exemplary alkyl groups include,but are not limited to, methyl, ethyl, isopropyl, n-propyl, n-butyl, andiso-butyl. Suitable haloalkyl groups for R¹ often have only a portion ofthe hydrogen atoms of the corresponding alkyl group replaced with ahalogen. Exemplary haloalkyl groups include chloroalkyl and fluoroalkylgroups with 1 to 3 halo atoms and 3 to 10 carbon atoms. Suitable alkenylgroups for R¹ often have 2 to 10 carbon atoms. Exemplary alkenyl groupsoften have 2 to 8, 2 to 6, or 2 to 4 carbon atoms such as ethenyl,n-propenyl, and n-butenyl. Suitable aryl groups for R¹ often have 6 to12 carbon atoms. Phenyl is an exemplary aryl group. The aryl group canbe unsubstituted or substituted with an alkyl (e.g., an alkyl having 1to 10 carbon atoms, 1 to 6 carbon atoms, or 1 to 4 carbon atoms), analkoxy (e.g., an alkoxy having 1 to 10 carbon atoms, 1 to 6 carbonatoms, or 1 to 4 carbon atoms), or halo (e.g., chloro, bromo, orfluoro). Suitable aralkyl groups for R¹ usually have an alkylene groupwith 1 to 10 carbon atoms and an aryl group with 6 to 12 carbon atoms.In some exemplary aralkyl groups, the aryl group is phenyl and thealkylene group has 1 to 10 carbon atoms, 1 to 6 carbon atoms, or 1 to 4carbon atoms (i.e., the structure of the aralkyl is alkylene-phenylwhere an alkylene is bonded to a phenyl group).

In some repeat units of Formula I (I-a or I-b), all R¹ groups can be oneof alkyl, haloalkyl, aralkyl, alkenyl, aryl, or aryl substituted with analkyl, alkoxy, or halo (e.g., all R¹ Groups are an alkyl such as methylor an aryl such as phenyl). In some compounds of Formula I, the R¹groups are mixtures of two or more selected from the group consisting ofalkyl, haloalkyl, aralkyl, alkenyl, aryl, and aryl substituted with analkyl, alkoxy, or halo in any ratio. Thus, for example, in certaincompounds of Formula I, 0%, 1%, 2%, 5%, 10%, 20%, 30%, 40%, 50%, 60%,70%, 80%, 90%, 95%, 98%, 99%, or 100% of the R¹ groups can be methyl;and 100%, 99%, 98%, 95%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10%,5%, 2%, 1%, or 0% of the R¹ groups can be phenyl.

In some repeat units of Formula I (I-a or I-b), at least 50 percent ofthe R¹ groups are methyl. For example, at least 60 percent, at least 70percent, at least 80 percent, at least 90 percent, at least 95 percent,at least 98 percent, or at least 99 percent of the R¹ groups can bemethyl. The remaining R¹ groups can be selected from an alkyl having atleast two carbon atoms, haloalkyl, aralkyl, alkenyl, aryl, or arylsubstituted with an alkyl, alkoxy, or halo.

Each Y in Formula I (I-a or I-b) is independently an alkylene,aralkylene, or a combination thereof. Suitable alkylene groups typicallyhave up to 10 carbon atoms, up to 8 carbon atoms, up to 6 carbon atoms,or up to 4 carbon atoms. Exemplary alkylene groups include methylene,ethylene, propylene, butylene, and the like. Suitable aralkylene groupsusually have an arylene group with 6 to 12 carbon atoms bonded to analkylene group with 1 to 10 carbon atoms. In some exemplary aralkylenegroups, the arylene portion is phenylene. That is, the divalentaralkylene group is phenylene-alkylene where the phenylene is bonded toan alkylene having 1 to 10, 1 to 8, 1 to 6, or 1 to 4 carbon atoms. Asused herein with reference to group Y, “a combination thereof” refers toa combination of two or more groups selected from an alkylene andaralkylene group. A combination can be, for example, a single aralkylenebonded to a single alkylene (e.g., alkylene-arylene-alkylene). In oneexemplary alkylene-arylene-alkylene combination, the arylene isphenylene and each alkylene has 1 to 10, 1 to 6, or 1 to 4 carbon atoms.

Each subscript n in Formula I (I-a or I-b) is independently an integerof 0 to 1500. For example, subscript n can be an integer up to 1000, upto 500, up to 400, up to 300, up to 200, up to 100, up to 80, up to 60,up to 40, up to 20, or up to 10. The value of n is often at least 1, atleast 2, at least 3, at least 5, at least 10, at least 20, or at least40. For example, subscript n can be in the range of 40 to 1500, 0 to1000, 40 to 1000, 0 to 500, 1 to 500, 40 to 500, 1 to 400, 1 to 300, 1to 200, 1 to 100, 1 to 80, 1 to 40, or 1 to 20.

The subscript p is an integer of 1 to 10. For example, the value of p isoften an integer up to 9, up to 8, up to 7, up to 6, up to 5, up to 4,up to 3, or up to 2. The value of p can be in the range of 1 to 8, 1 to6, or 1 to 4.

Group G in Formula I (I-a or I-b) is a residual unit that is equal to adiamine or polyamine compound of formula G(NHR³)_(q) minus the q aminogroups (i.e., —NHR³ groups), where q is an integer greater than or equalto 2. The diamine and/or polyamine can have primary and/or secondaryamino groups. Group R³ is hydrogen or alkyl (e.g., an alkyl having 1 to10, 1 to 6, or 1 to 4 carbon atoms) or R³ taken together with G and withthe nitrogen to which they are both attached forms a heterocyclic group(e.g., R³HN-G-NHR³ is piperazine). In most embodiments, R³ is hydrogenor an alkyl. In many embodiments, all of the amino groups of the diamineand/or polyamine are primary amino groups (i.e., all the R³ groups arehydrogen) and the diamine and/or polyamine are of the formula G(NH₂)_(q)(e.g., a diamine of the formula R³HN-G-NHR³ when q=2).

In certain embodiments, Group G in Formula I (I-a or I-b) is a mixtureof residual units that are equal to (i) a diamine compound of theformula R³HN-G-NHR³ minus the two amino groups (i.e., —NHR³ groups) and(ii) a polyamine compound of the formula G(NHR³)_(q) minus the q aminogroups (i.e., —NHR³ groups), where q is an integer greater than 2. Insuch embodiments, the polyamine compound of formula G(NHR³)_(q) can be,but is not limited to, triamine compounds (i.e., q=3), tetraaminecompounds (i.e., q=4), and combinations thereof. In such embodiments,the number of equivalents of polyamine (ii) per equivalent of diamine(i) is preferably at least 0.001, more preferably at least 0.005, andmost preferably at least 0.01. In such embodiments, the number ofequivalents of polyamine (ii) per equivalent of diamine (i) ispreferably at most 3, more preferably at most 2, and most preferably atmost 1.

When G includes residual units that are equal to (i) a diamine compoundof formula R³HN-G-NHR³ minus the two amino groups (i.e., —NHR³ groups),G can be an alkylene, heteroalkylene, polydiorganosiloxane, arylene,aralkylene, or a combination thereof. Suitable alkylenes often have 2 to10, 2 to 6, or 2 to 4 carbon atoms. Exemplary alkylene groups includeethylene, propylene, butylene, and the like. Suitable heteroalkylenesare often polyoxyalkylenes such as polyoxyethylene having at least 2ethylene units, polyoxypropylene having at least 2 propylene units, orcopolymers thereof. Suitable polydiorganosiloxanes includepolydiorganosiloxane diamines, minus the two amino groups. Exemplarypolydiorganosiloxanes include, but are not limited to,polydimethylsiloxanes with alkylene Y groups. Suitable aralkylene groupsusually contain an arylene group having 6 to 12 carbon atoms bonded toan alkylene group having 1 to 10 carbon atoms. Some exemplary aralkylenegroups are phenylene-alkylene where the phenylene is bonded to analkylene having 1 to 10 carbon atoms, 1 to 8 carbon atoms, 1 to 6 carbonatoms, or 1 to 4 carbon atoms. As used herein with reference to group G,“a combination thereof” refers to a combination of two or more groupsselected from an alkylene, heteroalkylene, polydiorganosiloxane,arylene, and aralkylene. A combination can be, for example, anaralkylene bonded to an alkylene (e.g., alkylene-arylene-alkylene). Inone exemplary alkylene-arylene-alkylene combination, the arylene isphenylene and each alkylene has 1 to 10, 1 to 6, or 1 to 4 carbon atoms.

In preferred embodiments, the polydiorganosiloxane polyamide is apolydiorganosiloxane polyoxamide. The polydiorganosiloxane polyoxamidetends to be free of groups having a formula —R^(a)—(CO)—NH— where R^(a)is an alkylene. All of the carbonylamino groups along the backbone ofthe copolymeric material are part of an oxalylamino group (i.e., the—(CO)—(CO)—NH— group). That is, any carbonyl group along the backbone ofthe copolymeric material is bonded to another carbonyl group and is partof an oxalyl group. More specifically, the polydiorganosiloxanepolyoxamide has a plurality of aminoxalylamino groups.

The polydiorganosiloxane polyamide can be a block copolymer and can bean elastomeric material. Unlike many of the known polydiorganosiloxanepolyamides that are generally formulated as brittle solids or hardplastics, the polydiorganosiloxane polyamides can be formulated toinclude greater than 50 weight percent polydiorganosiloxane segmentsbased on the weight of the copolymer. The weight percent of thediorganosiloxane in the polydiorganosiloxane polyamides can be increasedby using higher molecular weight polydiorganosiloxanes segments toprovide greater than 60 weight percent, greater than 70 weight percent,greater than 80 weight percent, greater than 90 weight percent, greaterthan 95 weight percent, or greater than 98 weight percent of thepolydiorganosiloxane segments in the polydiorganosiloxane polyamides.Higher amounts of the polydiorganosiloxane can be used to prepareelastomeric materials with lower modulus while maintaining reasonablestrength.

Some of the polydiorganosiloxane polyamides can be heated to atemperature up to 200° C., up to 225° C., up to 250° C., up to 275° C.,or up to 300° C. without noticeable degradation of the material. Forexample, when heated in a thermogravimetric analyzer in the presence ofair, the copolymers often have less than a 10 percent weight loss whenscanned at a rate 50° C. per minute in the range of 20° C. to 350° C.Additionally, the copolymers can often be heated at a temperature suchas 250° C. for 1 hour in air without apparent degradation as determinedby no detectable loss of mechanical strength upon cooling.

The copolymeric material having repeat units of Formula I (I-a or I-b)can be optically clear. As used herein, the term “optically clear”refers to a material that is clear to the human eye. An optically clearcopolymeric material often has a luminous transmission of at least 90percent, a haze of less than 2 percent, and opacity of less than 1percent in the 400 to 700 nm wavelength range. Both the luminoustransmission and the haze can be determined using, for example, themethod of ASTM-D 1003-95.

Additionally, the copolymeric material having repeat units of Formula I(I-a or I-b) can have a low refractive index. As used herein, the term“refractive index” refers to the absolute refractive index of a material(e.g., copolymeric material) and is the ratio of the speed ofelectromagnetic radiation in free space to the speed of theelectromagnetic radiation in the material of interest. Theelectromagnetic radiation is white light. The index of refraction ismeasured using an Abbe refractometer, available commercially, forexample, from Fisher Instruments of Pittsburgh, Pa. The measurement ofthe refractive index can depend, to some extent, on the particularrefractometer used. For some embodiments (e.g., embodiments in which thecopolymer includes a polydimethylsiloxane segment), the copolymericmaterial can have a refractive index in the range of 1.41 to 1.50. Forsome other embodiments (e.g., embodiments in which the copolymerincludes a polyphenylsiloxane or a polydiphenylsiloxane segment), thecopolymeric material can have a refractive index in the range of from1.46 to 1.55.

Polydiorganosiloxane polyamide block copolymers can optionally haveamide end-capped (e.g., oxalated) organic soft segments. In addition toat least one repeat unit of Formula I-a, such polymers can optionallyinclude at least one repeat unit of Formula II-a:

In this formula, R³, G, B, *, and q are as defined herein above, and Dis an organic soft segment residue. Each D is Formula II (II-a or II-b)represents an organic soft segment. Organic soft segments typicallyinclude one or more polyether residues such as, for example,polyoxyethylene residues, polyoxypropylene residues,poly(oxyethylene-co-oxypropylene) residues, and combinations thereof.The organic soft segment preferably has an average molecular weight ofat least 450, more preferably at least 700, and most preferably at least2000. The organic soft segment preferably has an average molecularweight of at most 8000, more preferably at most 6000, and mostpreferably at most 4000. A wide variety of organic soft segments can beused including, for example, those described in U.S. Pat. No. 4,119,615(Schulze).

Polydiorganosiloxane polyamides such as polydiorganosiloxane polyamideblock copolymers and polydiorganosiloxane polyoxamide block copolymerscan be prepared by methods known in the art. See, for example, U.S.Patent Application Publication Nos. 2007/0148474 A1 (Leir et al.) and2007/0149745 A1 (Leir et al.), and U.S. application Ser. Nos.11/821,571, 11/821,572, 11/821,575, and 11/821,596, all filed Jun. 22,2007.

Polydiorganosiloxane polyamide copolymers can be blended with one ormore other polymers (e.g., organic polymer components) such as a hotmelt processable thermoplastic polymer (which may be elastomeric ornonelastomeric), a hot melt processable elastomeric thermoset polymer, asilicone polymer, and mixtures thereof. See, for example, U.S. PatentApplication Publication No. 2007/0148475 A1 (Sherman et al.), and U.S.application Ser. No. 11/821,568, filed Jun. 22, 2007.

The organic polymer may be solvent or melt mixed with thepolydiorganosiloxane polyamide segmented copolymer. The organic polymermay be a polydiorganosiloxane polyamide-containing component or apolymer that does not contain polydiorganosiloxane segments.

Examples of suitable polydiorganosiloxane polyamide-containingcomponents include linear and/or branched polydiorganosiloxane polyamidecopolymers. An exemplary linear copolymeric material contains at leasttwo repeat units of Formula III-a:

In this formula, each R¹ is independently an alkyl, haloalkyl, aralkyl,alkenyl, aryl, or aryl substituted with an alkyl, alkoxy, or halo. EachY is independently an alkylene, aralkylene, or a combination thereof.Subscript n is independently an integer of 0 to 1500 and subscript p isan integer of 1 to 10. Group G is a divalent group that is the residueunit that is equal to a diamine of formula R³HN-G-NHR³ minus the two—NHR³ groups (i.e., amino groups). Group R³ is hydrogen or alkyl or R³taken together with G and with the nitrogen to which they are bothattached forms a heterocyclic group. Each B is independently a covalentbond, an alkylene of 4-20 carbons, an aralkylene, an arylene, or acombination thereof. Each asterisk indicates the position of attachmentof the repeating unit to another group such as another repeat unit.

A preferred copolymeric material contains at least two repeat units ofFormula III-b:

In this formula, each R¹ is independently an alkyl, haloalkyl, aralkyl,alkenyl, aryl, or aryl substituted with an alkyl, alkoxy, or halo. EachY is independently an alkylene, aralkylene, or a combination thereof.Subscript n is independently an integer of 0 to 1500 and subscript p isan integer of 1 to 10. Group G is a divalent group that is the residueunit that is equal to a diamine of formula R³HN-G-NHR³ minus the two—NHR³ groups (i.e., amino groups). Group R³ is hydrogen or alkyl or R³taken together with G and with the nitrogen to which they are bothattached forms a heterocyclic group. Each asterisk indicates theposition of attachment of the repeating unit to another group such asanother repeat unit.

Thermoplastic materials useful in the present invention that aregenerally considered nonelastomeric include, for example, polyolefinssuch as isotactic polypropylene, low density polyethylene, linear lowdensity polyethylene, very low density polyethylene, medium densitypolyethylene, high density polyethylene, polybutylene, nonelastomericpolyolefin copolymers or terpolymers, such as ethylene/propylenecopolymer and blends thereof; ethylene-vinyl acetate copolymers such asthat available under the trade designation ELVAX 260, available fromDuPont Chemical Co.; ethylene acrylic acid copolymers; ethylenemethacrylic acid copolymers such as that available under the tradedesignation SURLYN 1702, available from DuPont Chemical Co.;polymethylmethacrylate; polystyrene; ethylene vinyl alcohol; polyester;amorphous polyester; polyamides; fluorinated thermoplastics, such apolyvinylidene fluoride, polytetrafluoroethylene, fluorinatedethylene/propylene copolymers and fluorinated ethylene/propylenecopolymers; halogenated thermoplastics, such as a chlorinatedpolyethylene. Any single thermoplastic material can be mixed with atleast one branched polydiorganosiloxane polyamide-containing component.Alternatively, a mixture of thermoplastic materials may be used.

Thermoplastic materials that have elastomeric properties are typicallycalled thermoplastic elastomeric materials. Thermoplastic elastomericmaterials are generally defined as materials that act as though theywere covalently cross-linked, exhibiting high resilience and low creep,yet flow when heated above their softening point. Thermoplasticelastomeric materials useful in the present invention include, forexample, linear, radial, star and tapered styrene-isoprene blockcopolymers such as that available under the trade designation KRATOND1107P from Shell Chemical Co. of Houston, Tex. and that available underthe trade designation EUROPRENE SOL TE 9110 from EniChem ElastomersAmericas, Inc. of Houston, Tex.; linear styrene-(ethylene-butylene)block copolymers such as that available under the trade designationKRATON G1657 from Shell Chemical Co.; linearstyrene-(ethylene-propylene) block copolymers such as that availableunder the trade designation KRATON G1657X from Shell Chemical Co.;linear, radial, and star styrene-butadiene block copolymers such as thatavailable under the trade designation KRATON D1118X from Shell ChemicalCo. and that available under the trade designation EUROPRENE SOL TE 6205from EniChem Elastomers Americas, Inc.; polyetheresters such as thatavailable under the trade designation HYTREL G3548 from DuPont,elastomeric ethylene-propylene copolymers; thermoplastic elastomericpolyurethanes such as that available under the trade designationMORTHANE URETHENE PE44-203 from Morton International, Inc., Chicago,Ill.; self-tacky or tackified polyacrylates including C₃ to C₁₂alkylesters that may contain other comonomers, such as for example,isooctyl acrylate and from 0 to 20 weight percent acrylic acid;polyvinylethers; poly-α-olefin-based thermoplastic elastomeric materialssuch as those represented by the formula —(CH₂CHR)_(x) where R is analkyl group containing 2 to 10 carbon atoms and poly-α-olefins based onmetallocene catalysis such as that available under the trade designationENGAGE EG8200, an ethylene/poly-α-olefin copolymer, available from DowPlastics Co. of Midland, Mich.; as well as polydiorganosiloxanepolyurea-urethanes, available from Wacker Chemie AG, Germany under thetrade designation GENIOMER.

Thermoset elastomers (i.e., elastomeric thermosets) are materials thatchange irreversibly under the influence of heat from a fusible andsoluble material into one that is infusible and insoluble through theformation of a covalently cross-linked, thermally stable network.Thermoset elastomers useful in the present invention include, forexample, natural rubbers such as CV-60, a controlled viscosity gradeavailable from Goodyear Chemical, Akron, Ohio, and SMR-5, a ribbedsmoked sheet rubber; butyl rubbers, such as Exxon Butyl 268 availablefrom Exxon Chemical Co.; synthetic polyisoprenes such as that availableunder the trade designation CARIFLEX IR309 from Royal Dutch Shell ofNetherlands and that available under the trade designation NATSYN 2210from Goodyear Tire and Rubber Co.; styrene-butadiene random copolymerrubbers such as that available under the trade designation AMERIPOL1011A from BF Goodrich of Akron, Ohio; polybutadienes; polyisobutylenessuch as that available under the trade designation VISTANEX MM L-80 fromExxon Chemical Co.; polyurethanes such as, for example, polyoctadecylcarbamate disclosed in U.S. Pat. No. 2,532,011 (Dahlquist et al.);amorphous poly-α-olefins such as C₄-C₁₀ linear or branchedpoly-α-olefins; polydiorganosiloxane polyurea-containing components,such as those disclosed in U.S. Pat. No. 5,214,119 (Leir et al.).

Suitable silicone polymers are typically fluids and may be curable(through incorporation of suitable functional groups such as hydroxylgroups or ethylenically unsaturated groups, e.g., acrylate groups) orsubstantially noncurable. Examples of suitable silicone fluids aredescribed in, for example, International Application Publication No. WO97/40103 (Paulick et al.), U.S. Pat. No. 5,091,483 (Mazurek et al.) andU.S. Pat. No. 6,441,118 (Sherman et al.), and U.S. Patent ApplicationPublication No. 2005/0136266 (Zhou et al.). Particularly preferredsilicone polymers are moisture-curable silicone fluids, e.g.,hydroxyl-terminated polydiorganosiloxanes or nonreactive silicone fluidssuch as that available under the trade designation 47V1000 RHODORSILfrom Rhodia Silicones. Any of the hydroxyl-terminatedpolydiorganosiloxanes typically used in known silicone sealing andadhesive compositions may be used in the compositions of the presentinvention. Examples of suitable commercially available silicone fluidsinclude those available under the trade designation MASIL from LubrizolCorp. (Ohio) and Wacker Chemie AG (Germany).

Compositions and constructions as disclosed herein can also includefunctional components. Functional components such as antistaticadditives, ultraviolet light absorbers (UVAs), hindered amine lightstabilizers (HALS), dyes, colorants, pigments, antioxidants, slipagents, low adhesion materials, conductive materials, abrasion resistantmaterials, optical elements, dimensional stabilizers, adhesives,tackifiers, flame retardants, phosphorescent materials, fluorescentmaterials, nanoparticles, anti-graffiti agents, dew-resistant agents,load bearing agents, silicate resins, fumed silica, glass beads, glassbubbles, glass fibers, mineral fibers, clay particles, organic fibers,e.g., nylon, KEVLAR, metal particles, and the like which can be added inamounts up to 100 parts per 100 parts of the sum of the branchedpolydiorganosiloxane polyamide segmented polymeric component, providedthat if and when incorporated, such additives are not detrimental to thefunction and functionality of the final polymer product. Other additivessuch as light diffusing materials, light absorptive materials andoptical brighteners, flame retardants, stabilizers, antioxidants,compatibilizers, antimicrobial agents such as zinc oxide, electricalconductors, thermal conductors such as aluminum oxide, boron nitride,aluminum nitride, and nickel particles, including organic and/orinorganic particles, or any number or combination thereof can be blendedinto these systems. The functional components listed above may also beincorporated into polydiorganosiloxane polyamide block copolymerprovided such incorporation does not adversely affect any of theresulting product to an undesirable extent.

Fillers, tackifiers, plasticizers, and other property modifiers may beincorporated in the branched, polydiorganosiloxane polyamide segmentedorganic polymer. Tackifying materials or plasticizers useful with thepolymeric materials are preferably miscible at the molecular level,e.g., soluble in, any or all of the polymeric segments of theelastomeric material or the thermoplastic elastomeric material. Thesetackifying materials or plasticizers are generally immiscible with thepolydiorganosiloxane polyamide-containing component. When the tackifyingmaterial is present it generally comprises 5 to 300 parts by weight,more typically up to 200 parts by weight, based on 100 parts by weightof the polymeric material. Examples of tackifiers suitable for theinvention include but are not limited to liquid rubbers, hydrocarbonresins, rosin, natural resins such as dimerized or hydrogenated balsamsand esterified abietic acids, polyterpenes, terpene phenolics,phenol-formaldehyde resins, and rosin esters. Examples of plasticizersinclude but are not limited to polybutene, paraffinic oils, petrolatum,and certain phthalates with long aliphatic side chains such asditridecyl phthalate.

Either pressure sensitive adhesives or heat activated adhesives can beformulated by combining the polydiorganosiloxane polyoxamides with atackifier such as a silicate tackifying resin. As used herein, the term“pressure sensitive adhesive” refers to an adhesive that possesses thefollowing properties: (1) aggressive and permanent tack; (2) adherenceto a substrate with no more than finger pressure; (3) sufficient abilityto hold onto an adherend; and (4) sufficient cohesive strength to beremoved cleanly from the adherend. As used herein, the term “heatactivated adhesive” refers to an adhesive composition that isessentially non-tacky at room temperature but that becomes tacky aboveroom temperature above an activation temperature such as above 30° C.Heat activated adhesives typically have the properties of a pressuresensitive adhesive above the activation temperature.

Tackifying resins such as silicate tackifying resins are added to thepolydiorganosiloxane polyoxamide copolymer to provide or enhance theadhesive properties of the copolymer. The silicate tackifying resin caninfluence the physical properties of the resulting adhesive composition.For example, as silicate tackifying resin content is increased, theglassy to rubbery transition of the adhesive composition occurs atincreasingly higher temperatures. In some exemplary adhesivecompositions, a plurality of silicate tackifying resins can be used toachieve desired performance.

Suitable silicate tackifying resins include those resins composed of thefollowing structural units M (i.e., monovalent R′₃SiO_(1/2) units), D(i.e., divalent R′₂SiO_(2/2) units), T (i.e., trivalent R′SiO_(3/2)units), and Q (i.e., quaternary SiO_(4/2) units), and combinationsthereof. Typical exemplary silicate resins include MQ silicatetackifying resins, MQD silicate tackifying resins, and MQT silicatetackifying resins. These silicate tackifying resins usually have anumber average molecular weight in the range of 100 to 50,000 or in therange of 500 to 15,000 and generally have methyl R′ groups.

MQ silicate tackifying resins are copolymeric resins having R′₃SiO_(1/2)units (“M” units) and SiO_(4/2) units (“Q” units), where the M units arebonded to the Q units, each of which is bonded to at least one other Qunit. Some of the SiO_(4/2) units (“Q” units) are bonded to hydroxylradicals resulting in HOSiO_(3/2) units (“T^(OH)” units), therebyaccounting for the silicon-bonded hydroxyl content of the silicatetackifying resin, and some are bonded only to other SiO_(4/2) units.

Such resins are described in, for example, Encyclopedia of PolymerScience and Engineering, vol. 15, John Wiley & Sons, New York, (1989),pp. 265-270, and U.S. Pat. No. 2,676,182 (Daudt et al.), U.S. Pat. No.3,627,851 (Brady), U.S. Pat. No. 3,772,247 (Flannigan), and U.S. Pat.No. 5,248,739 (Schmidt et al.). Other examples are disclosed in U.S.Pat. No. 5,082,706 (Tangney). The above-described resins are generallyprepared in solvent. Dried or solventless, M silicone tackifying resinscan be prepared, as described in U.S. Pat. No. 5,319,040 (Wengrovius etal.), U.S. Pat. No. 5,302,685 (Tsumura et al.), and U.S. Pat. No.4,935,484 (Wolfgruber et al.).

Certain MQ silicate tackifying resins can be prepared by the silicahydrosol capping process described in U.S. Pat. No. 2,676,182 (Daudt etal.) as modified according to U.S. Pat. No. 3,627,851 (Brady), and U.S.Pat. No. 3,772,247 (Flannigan). These modified processes often includelimiting the concentration of the sodium silicate solution, and/or thesilicon-to-sodium ratio in the sodium silicate, and/or the time beforecapping the neutralized sodium silicate solution to generally lowervalues than those disclosed by Daudt et al. The neutralized silicahydrosol is often stabilized with an alcohol, such as 2-propanol, andcapped with R₃SiO_(1/2) siloxane units as soon as possible after beingneutralized. The level of silicon bonded hydroxyl groups (i.e., silanol)on the MQ resin may be reduced to no greater than 1.5 weight percent, nogreater than 1.2 weight percent, no greater than 1.0 weight percent, orno greater than 0.8 weight percent based on the weight of the silicatetackifying resin. This may be accomplished, for example, by reactinghexamethyldisilazane with the silicate tackifying resin. Such a reactionmay be catalyzed, for example, with trifluoroacetic acid. Alternatively,trimethylchlorosilane or trimethylsilylacetamide may be reacted with thesilicate tackifying resin, a catalyst not being necessary in this case.

MQD silicone tackifying resins are terpolymers having R′₃SiO_(1/2) units(“M” units), SiO_(4/2) units (“Q” units), and R′₂SiO_(2/2) units (“D”units) such as are taught in U.S. Pat. No. 2,736,721 (Dexter). In MQDsilicone tackifying resins, some of the methyl R′ groups of theR′₂SiO_(2/2) units (“D” units) can be replaced with vinyl (CH₂═CH—)groups (“D^(Vi)” units).

MQT silicate tackifying resins are terpolymers having R′₃SiO_(1/2)units, SiO_(4/2) units and R′SiO_(3/2) units (“T” units) such as aretaught in U.S. Pat. No. 5,110,890 (Butler) and Japanese Kokai HE2-36234.

Suitable silicate tackifying resins are commercially available fromsources such as Dow Corning, Midland, Mich., General Electric SiliconesWaterford, N.Y. and Rhodia Silicones, Rock Hill, S.C. Examples ofparticularly useful MQ silicate tackifying resins include thoseavailable under the trade designations SR-545 and SR-1000, both of whichare commercially available from GE Silicones, Waterford, N.Y. Suchresins are generally supplied in organic solvent and may be employed inthe formulations of the adhesives of the present invention as received.Blends of two or more silicate resins can be included in the adhesivecompositions.

The adhesive compositions typically contain 20 to 80 weight percentpolydiorganosiloxane polyoxamide and 20 to 80 weight percent silicatetackifying resin based on the combined weight of polydiorganosiloxanepolyoxamide and silicate tackifying resin. For example, the adhesivecompositions can contain 30 to 70 weight percent polydiorganosiloxanepolyoxamide and 30 to 70 weight percent silicate tackifying resin, 35 to65 weight percent polydiorganosiloxane polyoxamide and 35 to 65 weightpercent silicate tackifying resin, 40 to 60 weight percentpolydiorganosiloxane polyoxamide and 40 to 60 weight percent silicatetackifying resin, or 45 to 55 weight percent polydiorganosiloxanepolyoxamide and 45 to 55 weight percent silicate tackifying resin.

The adhesive composition can be solvent-free or can contain a solvent.Suitable solvents include, but are not limited to, toluene,tetrahydrofuran, dichloromethane, aliphatic hydrocarbons (e.g., alkanessuch as hexane), or mixtures thereof.

Polydiorganosiloxane polyamides with a small amount of branching can besoluble in many common organic solvents such as, for example, toluene,tetrahydrofuran, dichloromethane, aliphatic hydrocarbons (e.g., alkanessuch as hexane), or mixtures thereof. Polydiorganosiloxane polyamideswith higher amounts of branching can be swellable in many common organicsolvents such as, for example, toluene, tetrahydrofuran,dichloromethane, aliphatic hydrocarbons (e.g., alkanes such as hexane),or mixtures thereof.

The polydiorganosiloxane polyamides can be cast from solvents as film,molded or embossed in various shapes, or extruded into films. The hightemperature stability of the copolymeric material makes them well suitedfor extrusion methods of film formation. The films can be opticallyclear. A multilayer film containing the polydiorganosiloxane polyamideblock copolymers is further described in U.S. Patent ApplicationPublication No. 2007/0177272 A1 (Benson et al.).

In one or more embodiments, a polydiorganosiloxane polyamide containingmaterial having a structured surface can spontaneously and uniformlytransport liquids along the axis of channels. Two general factors thatcan influence the ability of a polydiorganosiloxane polyamide containingmaterial having a structured surface to spontaneously transport liquids(e.g., aqueous fluids and non-aqueous fluids such as organic fluids,silicone fluids, fluorocarbon fluids, and combinations thereof) are (i)the geometry or topography of the surface (e.g., capillarity, shape ofthe channels) and (ii) the nature of the film surface (e.g., surfaceenergy). To achieve the desired amount of fluid transport capability,the structure or topography of the microstructured surface can beadjusted and/or the surface energy of the microstructured surface can beadjusted. In order for a closed channel wick made from a microstructuredsurface to function it can be sufficiently hydrophilic to allow thedesired fluid to wet the surface. Generally, to facilitate spontaneouswicking in open channels, the fluid must wet the surface of themicrostructured surface, and the contact angle must be equal to or lessthan 90 degrees minus one-half the notch angle, as is describedhereinafter.

Generally, the susceptibility of a solid surface to be wet out by aliquid is characterized by the contact angle that the liquid makes withthe solid surface after being deposited on the horizontally disposedsurface and allowed to stabilize thereon. It is sometimes referred to asthe “static equilibrium contact angle,” and herein referred to as“contact angle.”

As shown in FIGS. 1a and 1b , the contact angle theta is the anglebetween a line tangent to the surface of a bead of liquid on a surfaceat its point of contact to the surface and the plane of the surface. Abead of liquid whose tangent was perpendicular to the plane of thesurface would have a contact angle of 90 degrees.

Typically, if the contact angle is 90 degrees or less, as shown in FIG.1a , the solid surface is considered to be wet by the liquid. Surfaceson which drops of water or aqueous solutions exhibit a contact angle ofless than 90 degrees are commonly referred to as “hydrophilic.” As usedherein, “hydrophilic” is used only to refer to the surfacecharacteristics of a material, i.e., that it is wet by aqueoussolutions, and does not express whether or not the material absorbsaqueous solutions.

Accordingly, a material can be referred to as hydrophilic whether or nota sheet of the material is impermeable or permeable to aqueoussolutions. Thus, hydrophilic microstructured surfaces can be formed frommaterials that are inherently hydrophilic. Liquids that yield a contactangle of near zero on a surface are considered to completely wet out thesurface. The contact angle of an inherently hydrophobic material withwater is typically greater than 90 degrees, such as shown in FIG. 1 b.

Microscopic features of a microstructured surface can have a widevariety of geometries. In one or more embodiments, a microscopic featurein a microstructured surface substantially retains its geometry andsurface characteristics upon exposure to liquids. The microstructuredsurface can also be treated to render the surface biocompatible. Forexample, a heparin coating can be applied to the surface.

The channels in microstructured surfaces can have a wide variety ofgeometries that provide for desired liquid transport properties. In oneor more embodiments, the channels in the microstructured surface providedesired liquid transport and are readily replicated.

Microscopic features can be in the shape of a channel (e.g., a groove)in the surface of a material. The cross section of such a channel canhave a wide variety of shapes (e.g., rectangular, V-shaped, round,etc.). Channels can also have cross-sections that are more complexshapes and can have grooves within grooves. Some examples ofcross-sectional shapes of channels that can be used in a deviceaccording to the present disclosure are described in U.S. Pat. No.6,420,622 (Johnston et al.).

The microstructured surfaces can have a variety of topographies. Forexample, microstructured surfaces can include a plurality of channelswith V-shaped or rectangular cross-sections, and/or combinations ofthese, as well as structures that have secondary channels, i.e.,channels within channels. Referring to FIG. 2, for open channels, adesired surface energy of the microstructured surface of V-channeledfluid control films can be such that:Theta≦(90°−Alpha/2),wherein theta (θ) is the contact angle of the liquid with the film andalpha (α) is the average included angle of the secondary V-channelnotches 2 within primary channel 1.

Depending on the nature of the microstructured material itself, and thenature of the fluid being transported, one may desire to adjust ormodify the microstructured surface in order to ensure sufficientcapillary forces of the microstructures. For example, themicrostructured surface can be modified in order to ensure it issufficiently hydrophilic. Liquids that will come into contact with themicrostructured surfaces can be aqueous. Thus, if such microstructuredsurfaces are used, they can be modified, e.g., by surface treatment,application of surface coatings or agents, or incorporation of selectedagents, such that the surface is rendered hydrophilic so as to exhibit acontact angle of 90 degrees or less, thereby enhancing the wetting andliquid transport properties of the microstructured surface. Suitablemethods of making the surface hydrophilic include: (i) incorporation ofa surfactant; (ii) incorporation or surface coating with a hydrophilicpolymer; (iii) treatment with a hydrophilic silane; or (iv) combinationsthereof. Other methods can also be envisioned.

A wide variety of methods can be utilized to achieve a hydrophilicmicrostructured surface. For example, in one embodiment surfacetreatments can be employed to render a microstructured surfacehydrophilic. Exemplary surface treatments include topical application ofa surfactant, plasma treatment, vacuum deposition, polymerization ofhydrophilic monomers, grafting hydrophilic moieties onto the surface,corona treatment, flame treatment, or combinations thereof. In anotherembodiment, a surfactant or other suitable agent can be blended with amaterial as an internal additive, and a surface of the material can thenbe structured. Exemplary surfactants and use of surfactants in fluidcontrol devices are disclosed in, for example, U.S. Pat. No. 6,420,622(Johnston et al.).

A microscopic feature of a microstructured surface can include, forexample, a well (e.g., a reservoir). Such a feature can be useful, forexample, to collect and/or retain fluids. A well can optionally beattached to a channel such that a fluid can flow from one into theother. For example, a well can receive fluids from one or more channels,provide fluids to one or more channels, or both. A well can have thesame depth as a channel or can have a different depth.

Referring now to FIG. 3, in one or more embodiments of the presentdisclosure, a device 5 includes a polydiorganosiloxane polyamidecontaining material 30 and has at least one microstructured surface 10(microscopic features not shown). The device 5 can include more than onemicrostructured surface 10.

Referring to FIG. 4, in some embodiments, a device 100 can include amaterial 130 that includes a polydiorganosiloxane polyamide containingmaterial and has two major surfaces 110 and 120. In one or moreembodiments, at least one major surface (110 and/or 120) of material 130is a structured (e.g., microstructured) surface. In one or moreembodiments, the device 100 can include a plurality of materials 130that include a polydiorganosiloxane polyamide containing material (e.g.,layers of material), with one, some, or all of the materials 130 havinga microstructured surface. Microstructured surfaces of materials 130 caneach include the same or different channel configurations and/or numberof channels, depending on a particular application.

In one or more embodiments, the microstructured surface of thepolydiorganosiloxane polyamide containing material includes at least onemicroscopic feature. Such microscopic features include, but are notlimited to, grooves, wells, and other architectures that can project outof and/or into the polydiorganosiloxane polyamide containing material.

In some embodiments, at least a portion of a microstructured surface 110and/or 120 of a polydiorganosiloxane polyamide containing material canhave hydrophilic characteristics. In other embodiments, at least aportion of a microstructured surface 110 and/or 120 of apolydiorganosiloxane polyamide containing material can have hydrophobiccharacteristics. Surface properties of a polydiorganosiloxane polyamidecontaining material can be modifiable to accommodate applicationsranging in need from hydrophobic to hydrophilic.

Referring to FIG. 5, in some embodiments, a device can be a fluidhandling device 200 that includes a polydiorganosiloxane polyamidecontaining material 230 attached to a substrate 220. The substrate 220can be attached to a structured surface 210 of polydiorganosiloxanepolyamide containing material 230. In such cases, the structured surface210 of polydiorganosiloxane polyamide containing material 230 andsubstrate 220 can, for example, form a fluid handling device 200. Such afluid handling device 200 can, for example, be a structured capillarydevice (i.e., having capillary-shaped structures or microstructures).

In some embodiments, a substrate 220, which is attached topolydiorganosiloxane polyamide containing material 230, includesconductive material (e.g., integrated circuitry). For example, thesubstrate can be a flexible circuit (i.e., a “flex circuit”), such as,for example, a film-based flexible circuit.

Referring to FIG. 6, another aspect of the present disclosure is a fluidhandling device 300 including a flex circuit 320. The flex circuit 320is attached to a structured material that includes polydiorganosiloxanepolyamide containing material 330. The polydiorganosiloxane polyamidecontaining material 330 can have a major surface having features, e.g.,a structured surface 310. In some embodiments, the flex circuit 320 isattached to the structured (e.g., microstructured) surface 310 of thepolydiorganosiloxane polyamide containing material 330.

Flex circuits generally include a flexible polymeric substrate materialhaving a quantity of a conductive material thereon or therein. A widevariety of polymeric materials having suitable flexible circuitsubstrate properties (e.g., dimensional stability, thermal resistance,tear resistance, and/or flexibility) can be used. For example, apolyester such as, for example, polyethylene terephthalate can be usedas a substrate in certain flexible circuit applications. A wide varietyof conductive materials can be used in the flexible circuit. In someembodiments, the conductive materials can include one of morenon-ferrous metals. For example, in certain embodiments gold, copper,nickel, tin, lead, and/or aluminum can be used in one or more flexiblecircuit applications. The conductive material can take the form ofintegrated circuitry, useful in various applications in which circuitsare used. Such applications can include, for example, fluid handlingapplications for use in diagnostic devices (e.g., medical diagnosticdevices), testing devices (e.g., environmental testing devices such asthose used, for example, in testing and/or purification of water and/ordevices testing for bacteria and/or pathogens in the food industry),actuation devices (e.g., fluid driven actuation devices), andcombinations thereof. In one or more embodiments of the presentdisclosure, devices can include none, one, or more than one flexiblecircuit.

Referring to FIG. 7, in some embodiments, a device 400 includes astructured material 430, at least a portion of which is adhered directlyto at least a portion of a substrate 420 that includes conductivematerial (not shown). Such conductive material can be integratedcircuitry, as in, for example, a flex circuit. As used herein, “adhereddirectly” means that there are no intervening materials (e.g., layers)between structured material 430 and substrate 420. In certainembodiments, at least a portion of structured material 430 is adhereddirectly to at least a portion of substrate 420 without using additionaladhesive. In one or more embodiments, device 400 includes no additionaladhesive at the interface of structured (e.g., microstructured) surface410 and major surface 440 of substrate 420. In certain embodiments, theinterface between the structured material 430 and the substrate 420having conductive material (e.g., integrated circuitry) can form afluid-tight seal without using additional adhesive.

In such a device 400, substrate 420 having conductive material (e.g.,integrated circuitry) can be a film-based flex circuit. A substrate 420having integrated circuitry (e.g., a film-based flex circuit) caninclude a polyester substrate. An exemplary polyester substrate is apolyethylene terephthalate substrate. In some embodiments, at least aportion of a polyethylene terephthalate substrate 420 is directlyadhered to at least a portion of a structured material 430 that includesone or more polydiorganosiloxane polyamides.

FIGS. 3-7 depict schematic representations of items having uniformthickness. For example, FIG. 3 depicts a polydiorganosiloxane polyamidecontaining material 30 having uniform thickness. However, while one ormore embodiments of the present disclosure can include apolydiorganosiloxane polyamide containing material 30 having a uniformthickness or substantially uniform thickness across a givenpolydiorganosiloxane polyamide containing material 30, it should benoted that one or more embodiments of the present disclosure can alsoinclude a polydiorganosiloxane polyamide containing material 30 havingnon-uniform thickness across a given polydiorganosiloxane polyamidecontaining material 30. Further, in a device 100 that includes, forexample, a plurality of polydiorganosiloxane polyamide containingmaterials 130 (e.g. a plurality of layers of polydiorganosiloxanepolyamide containing materials 130), each of the plurality ofpolydiorganosiloxane polyamide containing materials 130 can have eitheruniform, substantially uniform, or non-uniform thickness across aparticular polydiorganosiloxane polyamide containing material 130 andthe thickness of each polydiorganosiloxane polyamide containing material130 (e.g., layer) can be the same or different from onepolydiorganosiloxane polyamide containing material 130 to another. A“substantially uniform” thickness, as used herein, is used to describe avariation in thickness across a particular polydiorganosiloxanepolyamide containing material of no greater than 50%, and preferably nogreater than 25%, no greater than 10%, no greater than 5%, no greaterthan 2%, or even no greater than 1%. Similarly, items 30, 220, 230, 320,330, 420, and 430 in FIGS. 3 and 5-7 can each independently be uniform,substantially uniform, or non-uniform, and the thickness of each canindependently be the same or different.

Another aspect of the present disclosure is a method of making a fluidhandling device. The method includes providing a structured materialthat includes one or more polydiorganosiloxane polyamides and attachingthe structured material to a flex circuit. In some embodiments, the flexcircuit can be a film-based flex circuit. The flex circuit can include apolyester substrate such as, for example, a polyethylene terephthalatesubstrate.

Attaching a structured material to a flex circuit can be accomplishedusing a wide variety of methods known in the art. The structuredmaterial can be secured to the flex circuit by applying heat, forexample, as from an ultrasonic welding operation. For example, thestructured material, the flex circuit, or both can be heated. Theheating can be done either before or while contacting the structuredmaterial and the flex circuit. Attaching a structured material to a flexcircuit can include applying pressure such that the structured materialand the flex circuit are pressed together. Such pressure can be applied,for example, to the structured material. In some embodiments, a fluidtight seal is formed between the structured material and the flexcircuit as a result of heating and/or applying pressure.

Methods of manufacturing fluid handling devices with numerous layers ofraw materials and a number of process steps are known in the art. Forexample, the construction of a new layer in a fluid handling device canrequire a lithographic process such as photolithography in order todefine channel and well features. After photolithography, a wet chemicalprocessing step is typically employed to create channel and wellfeatures. One or more adhesives can optionally be applied to the itemhaving channel and well features for adhering to another component. Suchprocessing steps can be difficult and add to the complexity and cost ofmanufacturing the device. Methods of making devices according to thepresent disclosure can optionally avoid one or more potentiallydifficult processing steps or can optionally avoid use of one or moreadditional adhesives or other materials.

In one or more embodiments, methods of making a device according to thepresent disclosure optionally do not include applying or using anadditional adhesive between the structured material and the flexcircuit. Further, methods of making a device optionally do not includelithographic patterning (e.g., photolithographic patterning) of thestructured material (to define, for example, channel and/or wellfeatures) or wet chemical processing (to create, for example, channeland/or well features).

Another aspect of the present disclosure is a method of making a fluidhandling device. The method includes forming one or more microscopicfeatures in a surface of a polymeric material. Such a material caninclude, for example, one or more polydiorganosiloxane polyamides. Themethod further includes attaching the microstructured surface to a flexcircuit, as described above. The method can be performed with or withoutadditional adhesive between the microstructured surface and the flexcircuit.

In one or more embodiments, devices including a polydiorganosiloxanepolyamide containing material can be capable of controlling ortransporting a wide variety of fluids. Such fluids can be, for example,hydrophilic or hydrophobic. Such fluids can be, for example, aqueous(i.e., including water) or non-aqueous (i.e., not including water).Aqueous fluids include, but are not limited to, water and biologicalfluids such as blood, urine, wound exudates, food products stomachedinto a broth, and combinations thereof. Aqueous fluids can be, forexample, neutral, acidic, or basic. Non-aqueous fluids can include, forexample, a wide variety of organic fluids (such as, for example,alcohols, glycols, glycerols, polyalkylene glycols, esters, ethers,hydrocarbons, and combinations thereof), silicone fluids (such as, forexample, polydimethylsiloxanes, polyphenylmethylsiloxanes,polydiphenylsiloxanes, and combinations thereof), fluorocarbon fluids,and combinations thereof.

Such devices that include a polydiorganosiloxane polyamide containingmaterial can be fluid handling devices for use in diagnostic devices(e.g., medical diagnostic devices), testing devices (e.g., environmentaltesting devices such as those used, for example, in testing and/orpurification of water and/or devices testing for bacteria and/orpathogens in the food industry), actuation devices (e.g., fluid drivenactuation devices), and combinations thereof.

In one or more embodiments of the present disclosure, a device canfurther include one or more sources of potential. A wide variety ofsources of potential can be used to establish a potential differencealong a microstructured surface to encourage fluid movement from a firstlocation to a second location. The potential can be sufficient to cause,or assist in causing, fluid flow through one or more channels, based inpart on the fluid characteristics of a particular application. In one ormore embodiments, a device having a microstructured surface does notrely solely on the properties of the microstructured surface to causefluid movement by capillary action, for example. In some embodiments, apotential source can include a vacuum generator. Multiple potentialsources can also be employed depending on the particular adaptation orapplication. Pressure differential can be an efficient fluid motivationpotential that can be used to drive flow across the microstructuredsurface(s). Pressure differential can be established readily through useof pumping systems (e.g., pressure pumps and/or pressure systems such asa fan for elevated pressure) and/or vacuum systems (e.g., vacuum pumpsand/or vacuum aspirators for reduced pressure). Fluid can also be causedto flow through channels by the action of a siphon where atmosphericpressure creates the potential to move fluid in the channels.

Examples of other potential sources include but are not limited to,magneto hydrodynamic drives, acoustic flow systems, centrifugalspinning, hydrostatic heads, gravity, absorbents, other fluid drivesystems utilizing creation of a potential difference that causes orencourages fluid flow to at least to some degree, and combinationsthereof. Additionally, applied field forces that act directly on thefluid, such as a centrifugal force or a magnetic field, and that causefluid to move within the channels of the invention, can be considered asfluid motive potentials.

The individual flow channels of a microstructured surface can besubstantially discrete. That is, fluid can move through the channelsindependently of fluid in adjacent channels. The channels independentlyaccommodate the potential relative to one another to direct a fluidalong or through a particular channel independent of adjacent channels.For example, fluid that enters one flow channel may not, to asignificant degree, enter an adjacent channel, although there may besome diffusion between adjacent channels. It may be desired toeffectively maintain the discreteness of the channels in order toeffectively transport the fluid and maintain advantages that suchchannels provide. Not all channels, however, need be discrete for allembodiments. Some channels can be discrete while others are not.Additionally, channel “discreteness” can be a temporary phenomenondriven, for example, by fluctuating pressures.

The structured surface can be a microstructured surface that definesdiscrete flow channels that have a minimum aspect ratio(length/hydraulic radius) of 10:1, in some embodiments exceedingapproximately 100:1, and in other embodiments at least 1000:1. At thetop end, the aspect ratio could be indefinitely high but generally wouldbe less than 1,000,000:1. In certain embodiments, the hydraulic radiusof a channel is no greater than 300 micrometers. In many embodiments, itcan be less than 100 micrometers, and can be less than 10 micrometers.Although smaller is generally better for many applications (and thehydraulic radius could be submicron in size), the hydraulic radiustypically would not be less than 1 micrometer for many embodiments.

The structured surface can also be provided with a very low profile.Thus, active fluid transport devices are contemplated where thestructured polydiorganosiloxane polyamide layer has a thickness of lessthan 5000 micrometers, and possibly less than 1500 micrometers. To dothis, the channels can be defined by peaks that have a height ofapproximately 5 to 1200 micrometers and that have a peak distance of 10to 2000 micrometers.

Microstructured surfaces in accordance with the present disclosure canprovide flow systems in which the volume of the system is highlydistributed. That is, the fluid volume that passes through such flowsystems can be distributed over a large area. For example, channeldensity from 10 per lineal cm and up to 1,000 per lineal cm (measuredacross the channels) can provide for high fluid transport rates.

Fluid channels for use in the present invention can have a wide varietyof geometries, but are typically rectangular and sometimes have depthsof 50 to 3000 micron and widths of 50 to 3000 micron, or “V” channelpatterns and sometimes have depths of 50 to 3000 micron and heights of50 to 3000 micron with an included angle of generally 20 to 120 degreesand preferably 45 degrees. For example, a microstructured surface canhave a nested construction wherein the master channels are 200 microndeep and repeat every 225 micron with three equally spaced channels inthe base each 40 micron deep. Compound channels are also possible, suchas rectangular channels that contain smaller rectangular or V channelswithin. (See, e.g., FIG. 2.)

A suitable microstructured surface of a polydiorganosiloxane polyamidecontaining material can be made using methods such as casting,extrusion, injection molding, embossing, hot stamping, and combinationsthereof. In one method, a polydiorganosiloxane polyamide containingmaterial is deformed or molded. This process is usually performed at anelevated temperature and perhaps under pressure. The material can bemade to replicate or approximately replicate the surface structure of amaster tool. Since this process can produce relatively small structuresand is sometimes repeated many times over, the process is referred to asmicroreplication. Suitable processes for microreplication are described,for example, in U.S. Pat. No. 5,514,120 (Johnston et al.).

The following exemplary embodiments are provided by the presentdisclosure:

Embodiment 1

A device including a polydiorganosiloxane polyamide containing materialhaving a microstructured surface.

Embodiment 2

The device of embodiment 1, wherein the microstructured surface includesat least one channel.

Embodiment 3

The device of embodiment 1 or 2, wherein the microstructured surfaceincludes at least one well.

Embodiment 4

The device of any of embodiments 1 to 3, further including a flexcircuit attached to the microstructured surface.

Embodiment 5

The device of any of embodiments 1 to 4, wherein the device is a fluidhandling device.

Embodiment 6

The device of any of embodiments 1 to 5, wherein the microstructuredsurface forms a capillary device.

Embodiment 7

The device of any of embodiments 1 to 6, wherein the microstructuredsurface is hydrophilic.

Embodiment 8

A fluid handling device including: a flex circuit; and a structuredmaterial attached to the flex circuit, wherein the structured materialincludes one or more polydiorganosiloxane polyamides.

Embodiment 9

The fluid handling device of embodiment 8, wherein the structuredmaterial is a microstructured material.

Embodiment 10

The fluid handling device of embodiment 8 or 9, wherein the surface ofthe structured material that is attached to the flex circuit is amicrostructured surface.

Embodiment 11

The fluid handling device of any of embodiments 8 to 10, wherein thestructured material is adhered directly to at least a portion of theflex circuit.

Embodiment 12

The fluid handling device of any of embodiments 8 to 11, wherein thestructured material is adhered directly to at least a portion of theflex circuit without additional adhesive.

Embodiment 13

The fluid handling device of any of embodiments 8 to 12, furtherincluding a source of potential.

Embodiment 14

A method of making a fluid handling device, the method including:providing a structured material including one or morepolydiorganosiloxane polyamides; and attaching the structured materialto a flex circuit.

Embodiment 15

A method of making a fluid handling device, the method including:forming a microstructured surface on a surface of a polymeric materialincluding one or more polydiorganosiloxane polyamides; and attaching themicrostructured surface to a flex circuit.

Embodiment 16

The method of embodiment 14 or 15, wherein the flex circuit is afilm-based flex circuit.

Embodiment 17

A device or method according to any of claims 4 to 16, wherein the flexcircuit includes a polyester substrate.

Embodiment 18

A device or method according to any of claims 4 to 17, wherein the flexcircuit includes a polyethylene terephthalate substrate.

Embodiment 19

The method of any of embodiments 14 to 18, wherein attaching includesheating the structured material.

Embodiment 20

The method of any of embodiments 14 to 19, wherein attaching includesapplying pressure to the structured material.

Embodiment 21

The method of any of embodiments 14 to 20 with the proviso thatattaching does not include providing an additional adhesive materialbetween the structured material and the flex circuit.

Embodiment 22

The method of any of embodiments 14 to 21 with the proviso that themethod does not include photolithography.

Embodiment 23

The method of any of embodiments 14 to 22 with the proviso that themethod does not include a wet chemical process.

The foregoing describes the invention in terms of embodiments foreseenby the inventor for which an enabling description was available,notwithstanding that insubstantial modifications of the invention, notpresently foreseen, may nonetheless represent equivalents thereto.

EXAMPLES

These examples are merely for illustrative purposes only and are notmeant to be limiting on the scope of the appended claims. All parts,percentages, ratios, and the like in the examples are by weight, unlessnoted otherwise. Solvents and other reagents used were obtained fromSigma-Aldrich Chemical Company; Milwaukee, Wis. unless otherwise noted.

TABLE 1 Abbreviations Abbreviation or Trade Designation Description 14KPDMS A polydimethylsiloxane diamine with an average diamine molecularweight of about 14,000 g/mole that was prepared as described in U.S.Pat. No. 5,214,119 (Leir et al.) W3 14,000 MW Silicone Polyoxamide 5KPDMS A polydimethylsiloxane diamine with an average diamine molecularweight of about 5,000 g/mole that was prepared as described in U.S. Pat.No. 5,214,119 (Leir et al.) DEO Diethyl Oxalate ED Ethylene Diamine W15,000 MW Silicone Polyoxamide Primed PET 2 mil primed polyester filmfrom Mitsubishi GE SR545 A 60% solids solution of MQ silicate resin intoluene, MQ resin commercially available from GE Silicones; Waterford,NY under the trade designation SR545 T-10 release 2 mil polyester withsilicone release coating on one side liner from CP Films available fromSolutia, Inc., Fieldale, VA. substrate Any of a wide variety ofsubstrates including, for example,polymers, metals, inorganics,membranes, paper, and combinations thereof. MXDA Meta-xylylene diamineHD Hexane diamine THF Tetrahydrofuran W1-ED 5,000 MW siliconepolyoxamide elastomer polymerized with ethylene diamine W1-MXDA 5,000 MWsilicone polyoxamide elastomer polymerized with meta-xylylene diamineW1-HD 5,000 MW silicone polyoxamide elastomer polymerized with hexanediamine W2-ED 5,000 MW silicone polyoxamide elastomer polymerized withethylene diamine with 50% w/w GE SR545 MQ resin W2-MXDA 5,000 MWsilicone polyoxamide elastomer polymerized with meta-xylylene diaminewith 50% w/w GE SR545 MQ resin W3-ED 14,000 MW silicone polyoxamideelastomer polymerized with ethylene diamine W2-HD 5,000 MW siliconepolyoxamide elastomer polymerized with hexane diamine with 50% w/w GESR545 MQ resin

Titration Method to Determine Equivalent Weight of Ester-TerminatedSilicone Polyoxamide.

Ten (10) grams (precisely weighed) of an ester-terminated siliconepolyoxamide (e.g., the compound of Preparative Example 1, W1) was addedto a jar. Approximately 50 grams THF solvent (not precisely weighed) wasadded. The contents were mixed using a magnetic stir bar mix until themixture was homogeneous. The theoretical equivalent weight of theester-terminated silicone polyoxamide was calculated and then an amountof N-hexylamine (precisely weighed) in the range of 3 to 4 times thisnumber of equivalents was added. The reaction mixture was stirred for aminimum of 4 hours. Bromophenol blue (10-20 drops) was added and thecontents were mixed until homogeneous. The mixture was titrated to ayellow endpoint with 1.0N (or 0.1N) hydrochloric acid. The number ofequivalents of the ester-terminated silicone polyoxamide was equal tothe number of equivalents of N-hexylamine added to the sample minus thenumber of equivalents of hydrochloric acid added during titration. Theequivalent weight (grams/equivalent) was equal to the sample weight ofthe ester-terminated silicone polyoxamide divided by the number ofequivalents of the ester-terminated silicone polyoxamide.

Inherent Viscosity (IV) for Polydiorganosiloxane Polyoxamide BlockCopolymer.

Average inherent viscosities (IV) were measured at 30° C. using aCannon-Fenske viscometer (Model No. 50 P296) in a THF solution at 30° C.at a concentration of 0.2 grams per deciliter (g/dL). Inherentviscosities of the materials of the invention were found to beessentially independent of concentration in the range of 0.1 to 0.4g/dL. The average inherent viscosities were averaged over 3 or moreruns. Any variations for determining average inherent viscosities areset forth in specific Examples.

Preparative Example 1 (W1)

DEO (241.10 grams) was placed in a 3-liter, 3-neck resin flask equippedwith a mechanical stirrer, heating mantle, nitrogen inlet tube (withstopcock), and an outlet tube. The flask was purged with nitrogen for 15minutes and 5K PDMS diamine (a polydimethylsiloxane diamine with anaverage molecular weight of about 5,000 g/mole that was prepared asdescribed in Example 2 in U.S. Pat. No. 5,214,119 (Leir et al.))(2,028.40 grams, MW=4,918) was added slowly with stirring. After 8 hoursat room temperature, the reaction flask was fitted with a distillationadaptor and receiver, the contents stirred and heated to 150° C. undervacuum (1 Torr, 133 Pa) for 4 hours, until no further distillate wasable to be collected. The remaining liquid was cooled to roomtemperature to provide 2,573 grams of oxamido ester-terminated productW1. Gas chromatographic analysis of the clear, mobile liquid showed thatno detectable level of diethyl oxalate remained. Molecular weight wasdetermined by ¹H NMR (MW=5,477 grams/mole) and titration (Equivalentweights of 2,573 grams/mole and 2,578 grams/mole).

Preparative Example 2 (W1-Ed)

Into a 20° C. 10-gallon (37.85-Liter) stainless steel reaction vessel,18158.4 grams of 5K ethyl oxalylamidopropyl terminated polydimethylsiloxane (titrated MW=5,477, which was prepared in a fashion similar tothe description in the Preparative Example 1, with the volumes adjustedaccordingly) was placed. The vessel was subjected to agitation (80 rpm)and purged with nitrogen flow and vacuum for 15 minutes. The reactor wasthen nitrogen pressurized to 5 pounds per square inch and heated to 90°C. over the course of 25 minutes. ED (0.44 pound) was added to thereactor. This addition was followed by 80 grams of toluene. Next thereactor was heated to a temperature of 105° C. and the pressure on thereactor was slowly vented over the course of 5 minutes. The reactor wasthen subjected to vacuum (approximately 20 mm Hg, 2666 Pa) for one hourto remove the ethanol and toluene. The reactor was then re-pressurizedto 2 psig (13789 Pa) and the viscous molten product W1-ED was drainedinto a polytetrafluoroethylene-coated tray and allowed to cool.

Preparative Example 3 (W1-MXDA)

This example was prepared as in Preparative Example 2 except that 1.0mole % of the ED was replaced with an equal number of moles of MXDA tomake W1-MXDA.

Preparative Example 4 (W1-HD)

This example was prepared as in Preparative Example 2 except that 1.0mole % of the ED was replaced with an equal number of moles of HD togive W1-HD.

Preparative Example 5 (W2-ED)

W1-ED was blended with GE SR545 MQ resin in a 50/50 weight ratio insolvent at 30% solids to make W2-ED.

Preparative Example 6 (W2-MXDA)

W1-MXDA was blended with GE SR545 MQ resin in a 50/50 weight ratio insolvent at 30% solids to make W2-MXDA.

Preparative Example 7 (W2-HD)

W1-HD was blended with GE SR545 MQ resin in a 50/50 weight ratio insolvent at 30% solids to make W2-HD.

Example 1

W1-ED was dissolved in THF at 30% solids and coated onto primed PET, andoven-dried at 70° C. for 10 minutes to give a 0.001 inch (0.025 mm)thick dried coating. The sample was laminated to T-10 release liner.

Example 2

W1-MXDA was dissolved in THF at 30% solids and coated onto primed PET,and oven-dried at 70° C. for 10 minutes to give a 0.001 inch (0.025 mm)thick dried coating. The sample was laminated to T-10 release liner.

Example 3

W1-MXDA was dissolved in THF at 30% solids and coated onto primed PET,and oven-dried at 70° C. for 10 minutes to give a 0.003 inch (0.075 mm)thick dried coating. The sample was laminated to T-10 release liner.

Example 4

W1-HD was dissolved in THF at 30% solids and coated onto primed PET, andoven-dried at 70° C. for 10 minutes to give a 0.001 inch (0.025 mm)thick dried coating. The sample was laminated to T-10 release liner.

Example 5

W2-ED was coated onto primed PET, and oven-dried at 70° C. for 10minutes to give a 0.001 inch (0.025 mm) thick dried coating. The samplewas laminated to T-10 release liner.

Example 6

W2-MXDA was coated onto primed PET, and oven-dried at 70° C. for 10minutes to give a 0.001 inch (0.025 mm) thick dried coating. The samplewas laminated to T-10 release liner.

Example 7

W2-HD was coated onto primed PET, and oven-dried at 70° C. for 10minutes to give a 0.001 inch (0.025 mm) thick dried coating. The samplewas laminated to T-10 release liner.

Adhesive Test Procedure.

All samples were laminated using a roll lamination with heated, chromeplated, steel roll against an 80 durometer silicone rubber drive rolland pneumatic pressure. Lamination conditions were heat set point of200-250° F. (93-121° C.), 27.5 pounds per square inch (190 kilopascals)of pressure, and 1 inch/minute (2.54 cm/minute) speed. Each sample waslaminated in strips of approximately 2 inches (5 cm) in width then slitdown to approximately 8 mm wide strips. Eight mm strips were then peeledusing an Instron equipped with a German wheel/double stick tape pullsystem under the following parameters at 90° with a 1 kN load cell.

Table 2 summarizes the adhesion tests results. In general, adhesion ofthe silicone polyoxamide elastomer to the primed polyethyleneterephthalate film was light to moderate with the main trend being thatthicker samples, 0.003 inch (0.075 mm), provided better adhesion than0.001 inch (0.025 mm) thick samples.

TABLE 2 Adhesion Test Results Average Load/Width at average value Loadat (5 high and low Machine Maximum Width peaks) Peak Load Load/WidthExample (mm) (N/mm) (N) (N) 1 8.5 0.26 2.96 2.937 1 8.5 0.35 4.37 4.3462 7 0.424 4.322 4.322 2 7 0.528 4.298 4.298 3 6 0.994 7.379 7.379 3 70.87 9.101 9.027 3 10 0.562 7.934 7.934 4 6 0.495 4.059 4.06 4 7 0.4554.179 4.06 4 8 0.304 3.056 3.056

Water Traversal Times.

A 14,000 MW silicone polyoxamide elastomer polymerized with ED asprepared in Preparative Example 2 was embossed into an array of linearchannels where each channel was approximately 1 mm wide by 1 mm inheight. A single channel was cut from the array and cut to a length of 2cm. Tap water (80 microliters) was placed in a single drop on asubstrate that was located on a flat surface. The embossed channel wasplaced on the substrate with one end in contact with the water droplet.Table 3 lists the time it took for the water to traverse the channelversus the substrate on which the channel was placed (Table 3).

TABLE 3 Measured Water Traversal Times (seconds) Substrate Time (sec) tomove 2 cm Glass microscope slide <5 (VWR International, Cat. No.48312-002) 3M Magic tape (backing side) No movement 3M 355 tape (backingside) No movement Silicone wafer 113 +/− 10 Polystyrene No movement (VWRInternational, Petri dish, Disposable, Sterile, top surface) Valuesrepresent an average of three trials, and +/− is one standard deviation.

The experiment of Table 3 was duplicated but this time thesubstrate/channel assembly was held in a vertical orientation (asopposed to the flat orientation of Table 3). Table 4 lists the time ittook for the water to traverse the channel versus the substrate on whichthe channel was placed.

TABLE 4 Measured Water Traversal Times (seconds) Substrate Time (sec) tomove 2 cm Glass microscope slide <5 3M Scotch tape (backing side) <5 3M355 tape (backing side) <5 Silicone wafer <5 Polystyrene <5

This data demonstrates that the embossed channel can be used as a fluidtransport material. The rate of the transport for a given liquid willdepend on the substrate the channel is attached to and the gravitationalorientation to which the substrate is subjected.

The results of the embossing experiment showed that polydiorganosiloxanepolyamide materials could be embossed by using pressure and a low amountof heat. This work lead to the construction of a larger tool that wascapable of embossing an entire circuit. This mold was designed to bepressed into polydiorganosiloxane polyamide materials under highpressure and moderate heat, hence the thickness. Features on this moldincluded; channels 0.007 inch (0.18 mm) wide, 0.009 inch (0.23 mm) talland 1.00 inch (25 mm) long and circular wells 0.070 inch (1.8 mm) indiameter and 0.030 inch (0.76 mm) deep with a step leading into thechannel. It should be noted that the multi-level features, createdeasily with the process, are very difficult to produce using standard,layer built-up, processes typically used in fluid handling devices.

Initial attempts to create polydiorganosiloxane polyamide substratesthick enough to emboss with the new tool proved cumbersome usingavailable equipment. However, embossing is likely a viable method whenusing proper equipment.

A casting method was used to produce sample lots that were used forevaluation. In the casting process, molten silicone polyoxamideelastomer polymerized with ED as prepared in Preparative Example 2 wassimply poured over the mold, allowed to solidify, and removed. Thesolidified substrate removed nicely from the mold and produced clean,well formed channel and features.

Preparative Example 8

To a solution of 152.2 parts of methyl salicylate and 101.2 partstriethylamine in toluene (30%) was added dropwise with stirring a 40%solution of 91.5 parts of adipoyl chloride in toluene. An immediateprecipitate of triethylamine hydrochloride formed. Stirring wascontinued for 1 hour after addition was complete. The mixture wasfiltered, and the filtrate was evaporated to dryness in a rotaryevaporator to provide a white crystalline solid. The product wasisolated by slurrying in hexane and filtering and dried in an oven. Onlyone product was observed by thin layer chromatography (TLC) and bynuclear magnetic resonance (NMR) spectroscopy, the structure of theproduct was consistent with the diesterbis(2-carbomethoxyphenyl)adipate.

A 30% by weight solution of 526.0 parts of a 5K PDMS diamine and 11.6parts of hexamethylene diamine in isopropyl alcohol was prepared. A 30%by weight solution in isopropyl alcohol of 82.9 parts of the diesterbis(2-carbomethoxyphenyl)adipate as prepared as above was prepared andthis solution was added suddenly to the first solution. The clearsolution was stirred at room temperature overnight, during which timethe viscosity of the solution rose significantly. The solution was castinto a glass tray, the solvent allowed to evaporate over several hours,then dried in an oven at 70° C. overnight to provide a clear, strongelastomeric film of silicone polyadipamide. The silicone polyadipamidewas dissolved in a 50 wt % methyl ethyl ketone/50 wt % isopropanol blendat 10 wt % solids.

The complete disclosures of the patents, patent documents, andpublications cited herein are incorporated by reference in theirentirety as if each were individually incorporated. Variousmodifications and alterations to this invention will become apparent tothose skilled in the art without departing from the scope and spirit ofthis invention. It should be understood that this invention is notintended to be unduly limited by the illustrative embodiments andexamples set forth herein and that such examples and embodiments arepresented by way of example only with the scope of the inventionintended to be limited only by the claims set forth herein as follows.

What is claimed is:
 1. A testing device comprising: a flex circuit; anda structured material attached to the flex circuit, wherein thestructured material comprises one or more elastomericpolydiorganosiloxane polyoxamides.
 2. The testing device of claim 1,wherein the structured material is a microstructured material.
 3. Thetesting device of claim 2, wherein the surface of the structuredmaterial that is attached to the flex circuit is a microstructuredsurface.
 4. The testing device of claim 1, wherein the structuredmaterial is adhered directly to at least a portion of the flex circuit.5. The testing device of claim 4, wherein the structured material isadhered directly to at least a portion of the flex circuit withoutadditional adhesive.
 6. The testing device of claim 1, wherein the flexcircuit comprises a polyester substrate.
 7. The testing device of claim6, wherein the flex circuit comprises a polyethylene terephthalatesubstrate.
 8. The testing device of claim 1, further comprising a sourceof potential.
 9. The testing device of claim 1, wherein the testingdevice comprises an environmental testing device.
 10. The testing deviceof claim 1, wherein the testing device tests the purity of water, thepresence of bacteria in food, the presence of pathogens in food, or acombination thereof.
 11. A method of making a testing device, the methodcomprising: providing a structured material comprising one or moreelastomeric polydiorganosiloxane polyoxamides; and attaching thestructured material to a flex circuit.
 12. The method of claim 11,wherein the flex circuit is a film-based flex circuit.
 13. The method ofclaim 11, wherein the flex circuit comprises a polyester substrate. 14.The method of claim 13, wherein the flex circuit comprises apolyethylene terephthalate substrate.
 15. The method of claim 11,wherein attaching comprises heating the structured material.
 16. Themethod of claim 11, wherein attaching comprises applying pressure to thestructured material.
 17. The method of claim 11 with the proviso thatattaching does not comprise providing an additional adhesive materialbetween the structured material and the flex circuit.
 18. The method ofclaim 11 with the proviso that the method does not comprisephotolithography.
 19. The method of claim 11 with the proviso that themethod does not comprise a wet chemical process.
 20. A method of makinga testing device, the method comprising: forming a microstructuredsurface on a surface of a polymeric material comprising one or moreelastomeric polydiorganosiloxane polyoxamides; and attaching themicrostructured surface to a flex circuit.